Simulation of chloride ion transport in concrete under wetting-drying cycle
Simulation of chloride ion transport in concrete under wetting-drying cycle
复制标题
干湿循环下混凝土中氯离子传输模拟
DOI：
10.1080/21650373.2020.1722277
复制
发表时间：
2020-03-17
影响因子：
4.4
通讯作者：
Xu, Aoxue
中科院分区：
文献类型：
--
作者：
Cao, Tongning;Zhang, Lijuan;Xu, Aoxue
在氯化物腐蚀环境中，干湿交替区受有害介质侵蚀最为严重。首先，基于新的孔隙率和曲折度模型，考虑混凝土微观结构中水的传输与曲折度之间的相互作用，建立了水的非线性扩散-对流模型。其次，基于菲克第二定律，建立了干湿循环耦合作用下混凝土中氯离子传输的二维变系数模型。模型中充分考虑了影响输运的主要参数，如混凝土的孔隙率、弯曲度、饱和度和水泥的水化度。最后，采用交替方向隐式（ADI）方法对模型进行数值求解。结果表明，预测值与实验值相符。
In the corrosive environment of chloride, the drying-wetting alternating zones are most seriously eroded by harmful media. Firstly, based on the new porosity and tortuosity model, considering the interaction between the transport of water and the tortuosity in the concrete microstructure, a nonlinear diffusion-convection model of water is established. Secondly, a two-dimensional variable coefficient model of chloride ion transport in concrete under the coupled effects of drying-wetting cycles is established based on Fick's second law. The main parameters influencing transport in the proposed model such as porosity, tortuosity, saturation of concrete and hydration degree of cement are fully considered. Finally, the model is numerically solved by the alternating direction implicit (ADI) method. The results show that the values predicted agree with those of experiments.